Preparation, characterization and CO oxidation of nanometer Co3O4

Various nanometer Co3O4 samples were prepared and the catalytic performance of CO oxidation were examined. It was found that the activities of the catalysts were greatly changed with variation of the preparation methods and pretreatment conditions. Among the samples tested, Co3O4 prepared by using dodecylbenzene sulfonic acid sodium salt (DBS) as the surfactant, calcined at 300 degrees C showed the highest activity and it was able to oxidize completely CO even at -78 degrees C. Characterization of these samples by XRD and BET means showed that the catalytic activity increased with the decrease of the average particle size, suggests that the average particle size of nanometer Co3O4 samples is the main controlling factor of the catalytic activity.